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Share our site to support us! Please type an email. Please type a Name. I want more news and awesome tips. Our Reviews WizCase includes reviews written by our experts. Unless everyone has Microsoft Word installed on their computers, there's no guarantee that they would be able to open and view the newsletter.

And because Word documents are meant to be edited, there's a chance that some of the formatting and text in your document may be shifted around. By contrast, PDF files are primarily meant for viewing, not editing. One reason they're so popular is that PDFs can preserve document formatting , which makes them more shareable and helps them to look the same on any device. Sharing the newsletter as a PDF file would help ensure everyone is able to view it as you intended.

Opening and viewing a PDF file is pretty simple. The Times Square of years ago may have looked ecologically similar to the Times Square described by Welikia. Superficially, it probably resembled the old- growth forests that are still found in a few locations in the northeastern US. However, there would be some notable differences. There would be more large animals years ago. The forests of New York years ago would be full of chestnut trees.

Before a blight passed through in the early twentieth century, the hardwood forests of eastern North America were about 25 percent chestnut. Now, only their stumps survive. You can still come across these stumps in New England forests today. They periodically sprout new shoots, only to see them wither as the blight takes hold.

Someday, before too long, the last of the stumps will die. Wolves would be common in the forests, especially as you moved inland. There were no earthworms in New England when the European colonists arrived. The great ice sheets that covered New England had departed.

As of 22, years ago, the southern edge of the ice was near Staten Island, but by 18, years ago it had retreated north past Yonkers. The ice sheets scoured the landscape down to bedrock. Over the next 10, years, life crept slowly back northward.

As the ice sheets withdrew, large chunks of ice broke off and were left behind. Oakland Lake, near the north end of Springfield Boulevard in Queens, is one of these kettlehole ponds. Below the ice, rivers of meltwater flowed at high pressure, depositing sand and gravel as they went.

A hundred thousand years ago, Earth was near the end of a similar period of climate stability. To learn about those, we turn to the mystery of the pronghorn.

It can run at 55 mph, and sustain that speed over long distances. Yet its fastest predators, wolves and coyotes, barely break 35 mph in a sprint. Why did the pronghorn evolve such speed? A hundred thousand years ago, North American woods were home to Canis dirus the dire wolf , Arctodus the short-faced bear , and Smilodon fatalis sabre-toothed cat , each of which may have been faster and deadlier than modern predators.

Hyenas were mainly found in Africa and Asia, but when the sea level fell, one species crossed the Bering Strait into North America. The part of the continent that is now Manhattan was probably an inland region connected to what is now Angola and South Africa. In this ancient world, there were no plants and no animals. The oceans were full of life, but it was simple single-cellular life. On the surface of the water were mats of blue-green algae.

These unassuming critters are the deadliest killers in the history of life. Blue-green algae, or cyanobacteria, were the first photosynthesizers. They breathed in carbon dioxide and breathed out oxygen. Oxygen is a volatile gas; it causes iron to rust oxidation and wood to burn vigorous oxidation. The resulting extinction is called the oxygen catastrophe. We are the descendants of those first oxygen-breathers. Many details of this history remain uncertain; the world of a billion years ago is difficult to reconstruct.

Nobody knows when,12 but nothing lives forever. A million years is a long time. It seems reasonable to assume that however the human story plays out, in a million years it will have exited its current stage. Winds and rain and blowing sand will dissolve and bury the artifacts of our civilization. Eventually, the glaciers will advance again. Our plastic will become shredded and buried, and perhaps some microbes will learn to digest it, but in all likelihood, a million years from now, an out-of-place layer of processed hydrocarbons—transformed fragments of our shampoo bottles and shopping bags —will serve as a chemical monument to civilization.

The far future The Sun is gradually brightening. In a billion years, these feedback loops will have given out. They will have boiled away in the hot Sun, surrounding the planet with a thick blanket of water vapor and causing a runaway greenhouse effect. In a billion years, Earth will become a second Venus. Eventually, after several billion more years, we will be consumed by the expanding Sun. The Earth will be incinerated, and many of the molecules that made up Times Square will be blasted outward by the dying Sun.

If humans escape the solar system and outlive the Sun, our descendants may someday live on one of these planets. Atoms from Times Square, cycled through the heart of the Sun, will form our new bodies. One day, either we will all be dead, or we will all be New Yorkers. In his book , Charles C. There are a lot of problems with the concept of a single random soul mate. But of the 9.

Would we find each other? Right away, this would raise a few questions. For starters, would your soul mate even still be alive? If we were all paired up at random, 90 percent of our soul mates would be long dead. That sounds horrible. See, if your soul mate is in the distant past, then it also has to be possible for soul mates to be in the distant future. With the same-age restriction, most of us would have a pool of around half a billion potential matches.

But what about gender and sexual orientation? And culture? And language? Everybody would have only one orientation: toward their soul mate. The odds of running into your soul mate would be incredibly small. Given that you have ,, potential soul mates, it means you would find true love only in one lifetime out of 10, With the threat of dying alone looming so prominently, society could restructure to try to enable as much eye contact as possible.

We could put together massive conveyer belts to move lines of people past each other. I modeled a few simple systems to estimate how quickly people would pair off and drop out of the singles pool.

In the real world, many people have trouble finding any time at all for romance —few could devote two decades to it. So maybe only rich kids would be able to afford to sit around on SoulMateRoulette. If only 1 percent of the wealthy used the service, then 1 percent of that 1 percent would find their match through this system—one in 10, The other 99 percent of the 1 percent2 would have an incentive to get more people into the system.

But even if a bunch of us spent years on SoulMateRoulette, another bunch of us managed to hold jobs that offered constant eye contact with strangers, and the rest of us just hoped for luck, only a small minority of us would ever find true love. The rest of us would be out of luck.

Given all the stress and pressure, some people would fake it. A world of random soul mates would be a lonely one. The first thing to consider is that not everyone can see the Moon at once. We could try to illuminate either a new moon or a full moon. The new moon is darker, making it easier to see our lasers. The atmosphere would distort the beam a bit, and absorb some of it, but most of the light would make it. Half an hour after midnight GMT , everyone aims and presses the button.

It makes sense, though. Sunlight bathes the Moon in a bit over a kilowatt of energy per square meter. Just kidding! Memo to presidential candidates: This policy would win my vote. In addition to being more powerful, green laser light is nearer to the middle of the visible spectrum, so the eye is more sensitive to it and it seems brighter. The beam is several degrees wide, so we would want some focusing lenses to get it down to the half-degree needed to hit the Moon.

The beam is providing 20 lux of illumination, outshining the ambient light on the night half by a factor of two! Still barely visible. Good job, team. The Department of Defense has developed megawatt lasers, designed for destroying incoming missiles in mid-flight. The Boeing YAL-1 was a megawatt-class chemical oxygen iodine laser mounted in a The most powerful laser on Earth is the confinement beam at the National Ignition Facility, a fusion research laboratory.

Under those circumstances, it turns out Earth would still catch fire. The reflected light from the Moon would be four thousand times brighter than the noonday sun. But forget the Earth—what would happen to the Moon? The laser itself would exert enough radiation pressure to accelerate the Moon at about one ten millionth of a gee.

Forty megajoules of energy is enough to vaporize a kilogram of rock. Our laser would keep pouring more and more energy into the plasma, and the plasma would keep getting hotter and hotter. The particles would bounce off each other, slam into the surface of the Moon, and eventually blast into space at a terrific speed. This flow of material effectively turns the entire surface of the Moon into a rocket engine—and a surprisingly efficient one, too.

Using lasers to blast off surface material like this is called laser ablation, and it turns out to be a promising method for spacecraft propulsion. But if we make the wild guess that the particles in the plasma exit at an average speed of kilometers per second, then it will take a few months for the Moon to be pushed out of range of our laser.

This Earth-crossing orbit would lead to periodic unpredictable orbital perturbation. Scorecard: And that, at last, would be enough power. These collectors try to gather physical samples of as many of the elements as possible into periodic-table-shaped display cases. Another few dozen can be scavenged by taking things apart you can find tiny americium samples in smoke detectors. Others can be ordered over the Internet.

But what if you did? The periodic table of the elements has seven rows. The third row would burn you with fire. The fourth row would kill you with toxic smoke. The sixth row would explode violently, destroying the building in a cloud of radioactive, poisonous fire and dust.

Do not build the seventh row. The first row is simple, if boring: The cube of hydrogen would rise upward and disperse, like a balloon without a balloon. The same goes for helium. The second row is trickier. The lithium would immediately tarnish. The beryllium is pretty toxic, so you should handle it carefully and avoid getting any dust in the air. The neon floats away. Fluorine is the most reactive, corrosive element in the periodic table.

Almost any substance exposed to pure fluorine will spontaneously catch fire. You would definitely need a gas mask. Keep in mind that fluorine eats through a lot of potential mask materials, so you would want to test it first.

Have fun! On to the third row! The big troublemaker here is phosphorus. Pure phosphorus comes in several forms. Red phosphorus is reasonably safe to handle. White phosphorus spontaneously ignites on contact with air. It burns with hot, hard-to-extinguish flames and is, in addition, quite poisonous.

When exposed to pure fluorine gas, sulfur—like many substances—catches fire. The inert argon is heavier than air, so it would just spread out and cover the ground. You have bigger problems. The fire would produce all kinds of terrifying chemicals with names like sulfur hexafluoride.

On to row four! This is not one of those times. The burning phosphorus now joined by burning potassium, which is similarly prone to spontaneous combustion could ignite the arsenic, releasing large amounts of arsenic trioxide. That stuff is pretty toxic. This row would also produce hideous odors. Bromine is liquid at room temperature, a property it shares with only one other element—mercury. However, if you did this experiment from a safe distance, you might survive. The fifth row contains something interesting: technetium, our first radioactive brick.

If you spent all day wearing it as a hat—or breathed it in as dust —it could definitely kill you. Techneteium aside, the fifth row would be a lot like the fourth. On to the sixth row! No matter how careful you are, the sixth row would definitely kill you. These elements are normally shown separately from the main table to avoid making it too wide. Astatine is the bad one. Our cube would, briefly, contain more astatine than has ever been synthesized.

The heat alone would give third-degree burns to anyone nearby, and the building would be demolished. The cloud of hot gas would rise rapidly into the sky, pouring out heat and radiation. The explosion would be just the right size to maximize the amount of paperwork your lab would face. If it were larger, there would be no one left in the city to submit paperwork to. Dust and debris coated in astatine, polonium, and other radioactive products would rain from the cloud, rendering the downwind neighborhood completely uninhabitable.

The radiation levels would be incredibly high. Given that it takes a few hundred milliseconds to blink, you would literally get a lethal dose of radiation in the blink of an eye.

The seventh row would be much worse. There are a whole bunch of weird elements along the bottom of the periodic table called transuranic elements. They decay radioactively. And most of them decay into things that also decay. It would all happen at once. The flood of energy would instantly turn you—and the rest of the periodic table—to plasma. A mushroom cloud would rise over the city.

The top of the plume would reach up through the stratosphere, buoyed by its own heat. Entire regions would be devastated; the cleanup would stretch on for centuries. While collecting things is certainly fun, when it comes to chemical elements, you do not want to collect them all. O2 and N2. They cover the kinematics pretty well. This crowd takes up an area the size of Rhode Island. At the stroke of noon, everyone jumps.

Earth outweighs us by a factor of over ten trillion. On average, we humans can vertically jump maybe half a meter on a good day. Next, everyone falls back to the ground. A slight pulse of pressure spreads through the North American continental crust and dissipates with little effect.

The sound of all those feet hitting the ground creates a loud, drawn-out roar lasting many seconds. Eventually, the air grows quiet. Seconds pass. Everyone looks around. There are a lot of uncomfortable glances. Someone coughs. A cell phone comes out of a pocket. Outside Rhode Island, abandoned machinery begins grinding to a halt.

The T. Assuming they got things organized including sending out scouting missions to retrieve fuel , they could run at percent capacity for years without making a dent in the crowd.

Moments later, I, I, and I become the sites of the largest traffic jam in the history of the planet. Some make it past New York or Boston before running out of fuel. All the cops are in Rhode Island. The edge of the crowd spreads outward into southern Massachusetts and Connecticut. Any two people who meet are unlikely to have a language in common, and almost nobody knows the area.

Violence is common. Everybody is hungry and thirsty. Grocery stores are emptied. Within weeks, Rhode Island is a graveyard of billions. Our species staggers on, but our population has been greatly reduced. But at least now we know. First, some definitions. A mole is a unit. A mole is also a type of burrowing mammal. One pound is 1 kilogram. I happen to remember that a trillion trillion kilograms is how much a planet weighs. Mammals are largely water. A kilogram of water takes up a liter of volume, so if the moles weigh 4.

The cube root of 4. So doing this on Earth is definitely not an option. Gravitational attraction would pull them into a sphere. But this is where it gets weird. The mole planet would be a giant sphere of meat. Normally, when organic matter decomposes, it releases much of that energy as heat. Closer to the surface, where the pressure would be lower, there would be another obstacle to decomposition— the interior of a mole planet would be low in oxygen.

While inefficient, this anaerobic decomposition can unlock quite a bit of heat. If continued unchecked, it would heat the planet to a boil. But the decomposition would be self-limiting. Throughout the planet, the mole bodies would gradually break down into kerogen, a mush of organic matter that would—if the planet were hotter—eventually form oil. Because the moles form a literal fur coat, when frozen they would insulate the interior of the planet and slow the loss of heat to space. However, the flow of heat in the liquid interior would be dominated by convection.

Eventually, after centuries or millennia of turmoil, the planet would calm and cool enough that it would begin to freeze all the way through. The deep interior would be under such high pressure that as it cooled, the water would crystallize out into exotic forms of ice such as ice III and ice V, and eventually ice II and ice IX.

There might be a billion habitable planets in our galaxy. If you want a mole of moles, build a spaceship. All watts have to go somewhere. This is true of any device that uses power, which is a handy thing to know. Are they right? This is true of almost any powered device. At that temperature, the box will be losing heat to the outside as fast as the hair dryer is adding it inside, and the system will be in equilibrium.

If the box is made of metal, it will be hot enough to burn your hand if you touch it for more than five seconds. The temperature it reaches will depend on the thickness of the box wall; the thicker and more insulating the wall, the higher the temperature.

I wonder how high this dial goes. Two megawatts pumped into a laser is enough to destroy missiles. One more notch. Now 18 megawatts are flowing into the box. If it were steel, it would have melted by now.

The floor is made of lava. Before it can burn its way through the floor, someone throws a water balloon under it. The burst of steam launches the box out the front door and onto the sidewalk.

According to Back to the Future, the hair dryer is now drawing enough power to travel back in time. It sits in the middle of a growing pool of lava. Anything within 50— meters bursts into flame. A column of heat and smoke rise high into the air. Periodic explosions of gas beneath the box launch it into the air, and it starts fires and forms a new lava pool where it lands. We keep turning the dial. At In , H. Wells imagined devices like this in his book The World Set Free.

The story eerily foreshadowed the development, 30 years later, of nuclear weapons. The box is now soaring through the air. Each time it nears the ground, it superheats the surface, and the plume of expanding air hurls it back into the sky. I will definitely recommend this book to non fiction, science lovers. Great book, What If? Your Rating:. Your Comment:.